X-CGP-ClamAV-Result: CLEAN X-VirusScanner: Niversoft's CGPClamav Helper v1.23.0 (ClamAV engine v0.103.0) X-Junk-Score: 0 [] X-KAS-Score: 0 [] From: "Stephen Izett stephen.izett@gmail.com" Received: from mail-pf1-f178.google.com ([209.85.210.178] verified) by logan.com (CommuniGate Pro SMTP 6.3.5) with ESMTPS id 154451 for flyrotary@lancaironline.net; Tue, 20 Jul 2021 19:31:36 -0400 Received-SPF: pass receiver=logan.com; client-ip=209.85.210.178; envelope-from=stephen.izett@gmail.com Received: by mail-pf1-f178.google.com with SMTP id b12so829399pfv.6 for ; Tue, 20 Jul 2021 16:31:38 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:mime-version:subject:date:references:to:in-reply-to:message-id; bh=ECoYlvy8Rln0WUx5w/qHmpf7uqEhdV7TLzUCfQ7lcFs=; b=id0NPUDUKtDrqFKtyqb/UmR06z/wBdJI+s+zuRg60SxDUwd1V/RNNQIBakEEBFcpEe 4mA86512+IA4jgWYZ4+vE0S4K/g8hyufdL1mEYsLkSoJhJNFGV2eQfaBbXnl/8bs/Jvd +smZdRnXqqD9AdTyqK1FuzYV0ZE/37q2HiM8X6oVopFghOEutfxJTTcN9bEwdNOTfNqE 8SLiDuzU4c7nQ72VJzypQ/SJQZzxLpYznboptEA0O6iYKDm8U2RNZle4B4BWS5MxU9RJ PYhKD/QhiWfhKP6ijnwJVq0EkVdI1qX1Plyz1sAstWDr+YXziASfkKnIal9OO2LIXuGl BwIA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:mime-version:subject:date:references:to :in-reply-to:message-id; bh=ECoYlvy8Rln0WUx5w/qHmpf7uqEhdV7TLzUCfQ7lcFs=; b=n0WdAwE+elJIn3LFSK1AbXSpBI+onMSEH4VA8XgHQQL3suqmEvQK3h4RjXgIApz2Uk olAwDCRMoK1HRzq8TGr9S5Ue1U4q+lID+f9PHqqn2sH4bzxC4WIZJLW6+aPln/SgAPnX tGnRsD0uL+/CZJnDp0D4TpwG1m02dGarky+JO3ccxpoqtOtscDIfYUwz0G9ilzRaNeoB Hov5MJFsbgnK9Va7WhwQT3vpVGjP0njphv+PToJjOuUVQGABOFBEYWP6Y6EYEiKsLnHs L0AFnfQcS2p98T+wiT+53H7lPVthUHKmS1q2epc2VSTqxGDWFRYoW4rRj+uKIFu3F/yK Dmrg== X-Gm-Message-State: AOAM533wIH+Xm4Go3e42GA7GuHubdX+1RdPmoyJJ7byTBYi9i9HsivaI 06iqsiAdCf3zMxPe3H6dnM2Yyh0LxlI= X-Google-Smtp-Source: ABdhPJz+pJIbed/VI7yzZNBBGqI4Tiobt9F7M2GBC6MpS1r2ZJsr6oQ9nhXF0NndFZXJ4A40ypdfsQ== X-Received: by 2002:a05:6a00:1895:b029:32c:b091:ebc with SMTP id x21-20020a056a001895b029032cb0910ebcmr34709068pfh.4.1626823879914; Tue, 20 Jul 2021 16:31:19 -0700 (PDT) Return-Path: Received: from smtpclient.apple (220-235-119-136.dyn.iinet.net.au. [220.235.119.136]) by smtp.gmail.com with ESMTPSA id v15sm9115415pff.105.2021.07.20.16.31.17 for (version=TLS1_2 cipher=ECDHE-ECDSA-AES128-GCM-SHA256 bits=128/128); Tue, 20 Jul 2021 16:31:19 -0700 (PDT) Content-Type: multipart/alternative; boundary="Apple-Mail=_948636BB-084D-4BD6-B0F4-39E0A9ED7C0B" Mime-Version: 1.0 (Mac OS X Mail 14.0 \(3654.100.0.2.22\)) Subject: Re: [FlyRotary] Exhaust taming Date: Wed, 21 Jul 2021 07:31:13 +0800 References: To: Rotary motors in aircraft In-Reply-To: Message-Id: <2BAD8268-F15C-44B6-8541-4196FF458546@gmail.com> X-Mailer: Apple Mail (2.3654.100.0.2.22) --Apple-Mail=_948636BB-084D-4BD6-B0F4-39E0A9ED7C0B Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset=utf-8 Thanks Dave for the feedback.=20 I=E2=80=99ve never run it without the resonator (on the ground I mean). Perhaps I should try it and compare fuel flow/power at WOT. Cheers Steve > On 21 Jul 2021, at 2:33 am, David Leonard wdleonard@gmail.com = wrote: >=20 > Hi Steve, > For sure, Mild steel will not hold up in the early parts of the = rotary's exhaust system. 304 usually does pretty well, but I used 316 = whenever I could find the size and shape I needed in 316. In = particular, the welds on the 304 have needed touching up after 1200 hrs, = but the 316 is fine except for the welds to the turbo flange, which I = have also had to touch up. They eventually developed cracks and leaks. =20= >=20 > I have also tried a muffler similar to the one you show. It held up = fine to 20 or so flight hours, but there was a very noticeable power = loss so I removed it. >=20 > Best, > Dave Leonard >=20 > On Mon, Jul 19, 2021 at 6:10 PM Stephen Izett stephen.izett@gmail.com = > wrote: > Hi people >=20 > After only ~40 hours of flight + ground testing the mild steel 2.5=E2=80= =9D resonator in our system was looking a lilt worse for wear. > The leading edge of the internal auger/spiral was disintegrating. >=20 > We have purchased a 304 stainless version that=E2=80=99s an inch = longer and having it ceramic coated inside and out before reinstalling. >=20 > When I had the Glasair on the apron at full tilt the other day for = some tuning of the newly installed EC3, a guy=20 > commented on its noise being similar to other quiet Lycomings. As in = loudness, not pitch.=20 >=20 > I don=E2=80=99t know how much back pressure this type generates. Here = they are called a =E2=80=9CGonzo=E2=80=9D. They claim to be used in drag = rotary application. > Would be interesting to instrument it, but I don=E2=80=99t think I can = be bothered, as it seems to be developing good horsepower. >=20 > I expect this new stainless version will last much longer and be at = least as effective. > But the proof will be when I run it up and next annual. >=20 > Here are some photos >=20 > Cheers >=20 > Steve Izett > Glasair Super IIRG >=20 > >=20 > --Apple-Mail=_948636BB-084D-4BD6-B0F4-39E0A9ED7C0B Content-Transfer-Encoding: quoted-printable Content-Type: text/html; charset=utf-8 Thanks Dave for the feedback. 
I=E2=80=99ve= never run it without the resonator (on the ground I mean).
Perhaps I should try it and compare fuel flow/power at = WOT.

Cheers
Steve


On 21 Jul 2021, at 2:33 am, David Leonard wdleonard@gmail.com = <flyrotary@lancaironline.net> wrote:

Hi Steve,
For sure, Mild steel will not hold = up in the early parts of the rotary's exhaust system.  304 = usually does pretty well, but I used 316 whenever I could find the size = and shape I needed in 316.  In particular, the welds on the 304 = have needed touching up after 1200 hrs, but the 316 is fine except for = the welds to the turbo flange, which I have also had to touch up.  = They eventually developed cracks and leaks.  

I have also tried a = muffler similar to the one you show.  It held up fine to 20 or = so flight hours, but there was a very noticeable power loss so I = removed it.

Best,
Dave Leonard

On Mon, Jul 19, 2021 at 6:10 PM Stephen Izett stephen.izett@gmail.com <flyrotary@lancaironline.net> wrote:
Hi people

After only ~40 hours of flight + ground testing the mild = steel 2.5=E2=80=9D resonator in our system was looking a lilt worse for = wear.
The leading edge of the internal auger/spiral = was disintegrating.

We have purchased a 304 stainless version that=E2=80=99s an = inch longer and having it ceramic coated inside and out before = reinstalling.

When I had the Glasair on the apron at full tilt the other = day for some tuning of the newly installed EC3, a guy 
commented on its noise being similar to other quiet = Lycomings. As in loudness, not pitch. 

I don=E2=80=99t know how much back = pressure this type generates. Here they are called a =E2=80=9CGonzo=E2=80=9D= . They claim to be used in drag rotary application.
Would be interesting to instrument it, but I don=E2=80=99t = think I can be bothered, as it seems to be developing good = horsepower.

I = expect this new stainless version will last much longer and be at least = as effective.
But the proof will be when I run it = up and next annual.

Here are some photos

Cheers

Steve Izett
Glasair = Super IIRG

<DSCN0026.jpg>

<IMG_0471.jpeg><IMG_0467.jpeg>

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